A Recursive Method for Minimal Siphon Enumeration in Petri Nets

The enumeration of minimal siphons in ordinary Petri nets is fundamental in the assessment of behavioral properties and a crucial step in the development of deadlock prevention algorithms. A novel recursive algorithm is proposed in the paper for this purpose, based on theoretical results that extend well known properties described in the literature. The algorithm uses already found solutions to progressively decompose the search problem into smaller sub-problems. This recursive decomposition approach is combined with the LTUR procedure, which efficiently computes a siphon, based on a logical clause description approach. A prototypical version of the search algorithm has been developed and an experiment has been carried out on a large set of random test instances to evaluate the efficiency of the method.